Bicycle frame



FIG. 1 is a perspective view of a bicycle frame showing our new design,it being understood that the broken lines are for illustrative purposesonly and form no part of the claimed design;

FIG. 2 is a side elevational view thereof, the opposite side beingidentical thereto;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a front elevational view thereof;

FIG. 6 is a rear elevational view thereof.

The ornamental design for a bicycle frame, as shown and described.